Ó Fionnagáin
Ó FIONNAGÁIN—I—O Finegane, O Fenegane, Finnigan, Finnegan, Finigan, Finegan, Fanagan; 'descendant of Fionnagán' (diminutive of fionn, fair); the name (1) of a family of Ui Fiachrach, in Co. Mayo, and (2) of a Breifney family. At the end of the 16th century there were O'Finegans in all the provinces.
Alphabetical Index to Irish Surnames